Fundamentals of Pathology - Growth Adaptations

These flashcards cover essential concepts related to growth adaptations in pathology, including definitions, examples, and key physiological processes.

What is homeostasis in relation to an organ and physiologic stress?

Homeostasis refers to the state in which an organ is balanced and effectively functioning under the physiologic stress placed on it.

What are hyperplasia and hypertrophy?

Hyperplasia is the increase in the number of cells, while hypertrophy is the increase in the size of existing cells, both leading to an increase in organ size due to increased stress.

What is the key difference between hypertrophy and hyperplasia?

Hypertrophy involves an increase in cell size; hyperplasia involves an increase in cell number.

What leads to hypertrophy at the cellular level?

Hypertrophy involves gene activation, protein synthesis, and the production of organelles, such as mitochondria.

Can you give an example of hypertrophy?

During pregnancy, the smooth muscle of the uterus increases in size due to both hypertrophy and hyperplasia.

What are permanent tissues, and can they undergo hyperplasia?

Permanent tissues such as cardiac myocytes, skeletal muscle, and nerve cannot undergo hyperplasia due to a lack of stem cells and can only undergo hypertrophy.

What is pathologic hyperplasia and its potential consequence?

Pathologic hyperplasia occurs due to an underlying pathological process and can progress to dysplasia and cancer.

What is atrophy?

Atrophy is the decrease in organ size due to decreased stress, which can occur through decreased cell number (apoptosis) or decreased cell size.

What are the two primary mechanisms of atrophy?

Atrophy can occur through the ubiquitin-proteasome degradation pathway or through autophagy.

What causes metaplasia in an organ?

Metaplasia occurs when there is a change in stress on an organ, leading to a change in its cell type to better handle the new stress.

What is Barrett's esophagus?

Barrett's esophagus is an example of metaplasia where the lower esophagus's squamous epithelium changes to columnar epithelium due to acid reflux.

Is metaplasia reversible?

Yes, metaplasia is reversible if the underlying stressor is removed.

What is dysplasia?

Dysplasia refers to disordered cell growth, often considered a precancerous stage.

How does dysplasia relate to hyperplasia and cancer?

Dysplasia can arise from long-standing pathologic hyperplasia and can progress to cancer if the stress persists.

What is the difference between dysplasia and cancer?

Dysplasia is reversible if the underlying stress is removed, while cancer is irreversible.

What is aplasia?

Aplasia refers to the failure of an organ or tissue to develop properly, often occurring during embryogenesis.

What is hypoplasia?

Hypoplasia is the underdevelopment or incomplete development of an organ or tissue, resulting in a smaller size.